Thermionic device



H. J. ROUND.

THERMIONIC DEVICE.

APPLICATION FILED MAY 21. 1920.

1,361,099. Patented Dec. 7, 1920.

Henr f d 2, 1M MM 4 farny UNITED STATES PATENT OFFICE.

HENRY JOSEPH ROUND, 0]? LONDON, ENGLAND, ASSIGNOR T0 RADIO CORPORATION I OF AMERICA, A CORPORATION OF DELAWARE.

THERMIONIG DEVICE.

Specification of Letters Patent.

Patented Dec. 7, 1920.

Application filed May 21, 1920. Serial N0. 383,281.

To all whom it may] concern:

Be it known that I, HENRY JOSEPH ROUND, a subject ofmthe King of Great Britain, and resident of 9 VVoodberry Crescent, Muswell Hill, London, England, have invented'new and useful Improvements in Thermionic Devices, of which the following is. a specipanying drawing which is a section of a valve.

A is a hollow metal tube closed at its inner end and sealed at B into the glass of the bulb C and acting as the anode. It is surrounded by a grid D the lead from which passes out through the glass at E. F is a filament which is arranged preferably *as a coil around the grid and is maintained in position by supports G, the leads fromit being sealed through the glass at H. I is a.

- ing the glass. In some cases this sheath may be provided with a negative charge of electricity and the connection K may be used for this purpose.

In place of forming the filament as a single coil I may construct it in many other ways as the invention is not limited to specific constructions.

WVhat I claim is-: g

1. In a thermionic device, the combination of an anode, a grid surrounding the anode, a filament surrounding the grid and a metal sheath surrounding the filament.

2. In a thermionic device, the combination of an anode, means for cooling it, a grid surrounding the anode, a filament surrounding the grid and a metal sheath surrounding the filament.

3. Ina thermionic device, the combination of a hollow anode, means for. leading cooling fluid thereto, a grid surrounding the anode, a filament surrounding the grid and a metal sheath surrounding the filament.

In testimony that I claim the foregoing as my invention I have signedmy name this third day of May 1920.

HENRY JOSEPH ROUN D. 

